When we look at couples who are happily married, it’s obvious — and not just from the selfies they’re posting on Instagram. They’re supportive, communicate well, make each other laugh, the list goes on.

But what about all of the bizarre details that affect the quality marriage? According to science, there’s tons of random things that lead to happier marriages. Here are six you definitely didn’t know.

1. Having A Big WeddingWhat?! National Marriage Project from The University of Virginia conducted a survey involving American married couples to find correlations between happy marriages and the couple’s past. One thing that came up was the type of weddings they held. After using a sample of 418 couples, there was a correlation between formal weddings and greater conjugal happiness along with higher marital quality. But before you go all bridezilla and hire Coldplay as your wedding band, “bigger weddings” in this study were determined just by the number of guests — not by how extravagant they were.

2. Having High Bone Mineral DensityIn a study of 632 adults, a correlation between better bone health and marriage quality was found. Guys who never said “I do,” were separated, divorced, or widowed had significantly lower bone mass density. The researchers only found a correlation between these two factors — so we don’t know what caused this. Until we do, you may want to include milk on date nights.

3. Having An Attractive WifeShould we be surprised? A study led by psychologist Andrea Meltzer followed 450 newlywed couples over four years. He then asked them whether an attractive spouse leads to satisfaction in marriage. Men said yes, but the ladies said no. That’s kind of depressing …

4. Having An UNattractive HusbandAs for the huband’s looks? A study found that ladies are better off marrying down. Researchers believe it’s because the more unattractive husband would treat the more attractive wife better since men value beauty highly. This might be even more depressing…

5. Doing Hobbies SeparatelyHow important are common interests? Once you get married you might feel the need to do everything together, but if one person in the relationship actually doesn’t appreciate the hobby then it’s better to go solo. According to a study published in Journal of Marriage and Family, couples who separate to do hobbies have greater marriage satisfaction.

6. Putting Off BabiesWhen you ask parents how children affected their marriage they say their bond was strengthened, but a recent survey found young, childless couples are the have the happiest relationships. This isn’t very surprising when you consider how much work it takes to parent.